1. Field
One or more aspects of the disclosed embodiment relate to a lens optical system and an imaging device.
2. Brief Description of the Related Developments
Recently, the use and application of cameras including solid-state imaging devices such as complementary metal oxide semiconductor (CMOS) image sensors or charge coupled devices (CCDs) have greatly increased.
Also, the degree of pixel integration in solid-state imaging devices has increased to improve the resolution of cameras. Along with this, small and lightweight cameras have been developed by improving the performance of lens optical systems included in the cameras. Recently, imaging devices including solid-state imaging devices have been applied to mobile devices such as smartphones because such imaging devices are suitable for miniaturization. Particularly, automobiles require cameras and optical systems for various purposes such as forward monitoring, backward monitoring, lane recognition, or autonomous driving. In addition, various action cameras such as drones or camcorders for leisure or sports activities have been developed. In addition, lens optical systems and solid-state imaging devices are applied to fingerprint recognition devices. Since fingerprint recognition devices are used in various fields requiring authentication such as entrance control, electronic commerce, financial transaction, personal computer security, or business approval systems, research has been conducted into imaging devices and optical systems for fingerprint recognition devices.
In general, the optical performance of a camera may be guaranteed by using many lenses in the camera. In this case, however, it is difficult to reduce the size, weight, and manufacturing costs of the camera. On the other hand, if the number of lenses included in a camera is decreased, aberrations may not be sufficiently corrected even though it may be effective in terms of product sizes and price competitiveness.
In general, existing lens optical systems used in camera phones have a field of view (FOV) within the range of about 60° to about 65°. Therefore, there is a need for a small, wide-FOV lens optical system having improved properties such as a high aberration correcting ability and a high degree of resolution.